Waterproof case for in-vehicle camera

ABSTRACT

A waterproof case for an in-vehicle camera includes a front case part and a rear case part, and houses imaging means such as the imaging device therein. A packing member is set between the front case part and the rear case part, and waterproofs and seals the space therebetween. A water-stop wall part is protrudingly formed on a flange part which is an attaching portion of the rear case part at a peripheral of the packing member. A concave part, into which the water-stop wall part can be fitted, is formed on an opening peripheral part which is an attaching portion of the front case part.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a technique for waterproofing an in-vehicle camera provided outside a vehicle.

2. Description of the Related Art

There is a technique to take an image of periphery of a vehicle, particularly a dead zone, with an in-vehicle camera provided outside the vehicle and to display the image on a display apparatus inside the vehicle.

Since such in-vehicle camera is provided outside the vehicle body, it is required to have a sufficient waterproof property.

In a general waterproof structure of such in-vehicle camera, a packing is held between a front case and a rear case, which constitutes an outer part of the in-vehicle camera, and the cases are screwed shut.

However, in such waterproof structure, since a packing is compressed and disposed between the front case and the rear case, a small clearance is formed in an attaching portion between the front case and the rear case. Accordingly, when washing a vehicle with high pressure, an injection water of high pressure may directly hit the packing. In such case, there is a problem that the packing is pressed inwardly by the water pressure, whereby a waterproof property is deteriorated.

SUMMARY OF THE INVENTION

It is an object of the invention is to provide a waterproof case for an in-vehicle camera having an excellent waterproof property.

According to a first aspect of the invention, there is provided a waterproof case for an in-vehicle camera including: a first case part; a second case part which forms a case body with the first case part so as to house imaging means; a packing member set between the first case part and the second case part; and a water preventing section provided between the first case part and the second case part, wherein the packing member waterproofs and seals the space between the first case part and the second case part, and the water preventing section prevents the packing member from being exposed to water outside.

According to a second aspect of the invention, as set forth in the first aspect of the invention, the water preventing section may include: a water-stop wall part protrudingly formed on an attaching portion of the first case part at an outer peripheral of the packing member; and a concave part formed on an attaching portion of the second case part, wherein the water-stop wall part can be fitted in the concave part.

According to a third aspect of the invention, as set forth in the second aspect of the invention, the water-stop wall part may be fitted to the concave part such that a positional relation of the first case part and the second case part is maintained constant.

According to a fourth aspect of the invention, as set forth in the second aspect of the invention, the first case part may include a lens holding cylinder part which holds a imaging lens of the in-vehicle camera.

According to a fifth aspect of the invention, as set forth in the second aspect of the invention, the second case part may include a lens holding cylinder part which holds a imaging lens of the in-vehicle camera.

According to a sixth aspect of the invention, as set forth in the first aspect of the invention, the water preventing section may be provided at an outer peripheral of the packing member.

According to a seventh aspect of the invention, as set forth in the first aspect of the invention, a packing housing groove may be formed on one of the first case part or the second case part, wherein the packing member is housed in the packing housing groove such that the packing member protrudes from the packing housing groove.

According to an eighth aspect of the invention, as set forth in the first aspect of the invention, the first case part and the second case part may be fixed together with a screw.

According to a ninth aspect of the invention, as set forth in the second aspect of the invention, the water-stop wall part may be intermittently projected from the attaching portion of the first case part.

According to the waterproof case for an in-vehicle camera described above, since the water preventing section, which prevents the packing member from being exposed to the water outside, is provided between the first case part and the second case part, the case where high pressure injection water directly reaches a packing member at the time of washing a car by high pressure can be efficiently prevented. Accordingly, an excellent waterproof property can be obtained.

Further, when the water preventing section includes the water-stop wall part protrudingly formed on the attaching portion of the first case part at the outer peripheral of the packing member, and the concave part formed on the attaching portion of the second case part, wherein the water-stop wall part can be fitted in the concave part, the clearance between the attaching portion of the first case part and the attaching portion of the second case part can be made as small as possible. Accordingly, an excellent waterproof property can be obtained, and comparatively compact structure can be realized.

Further, when the water-stop wall part may be fitted to the concave part such that a positional relation of the first case part and the second case part is maintained constant, defects causing by a change of positional relation of the first case part and the second case part, such as a change of a viewing scope, can be efficiently prevented.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view showing a waterproof case for a camera apparatus according to an exemplary embodiment of the invention;

FIG. 2 is a partially-cut sectional view showing a waterproof case for a camera apparatus according to the exemplary embodiment of the invention;

FIG. 3 is an exploded perspective view of a waterproof case for a camera apparatus as viewed from a side of a front face thereof according to the exemplary embodiment of the invention; and

FIG. 4 is an exploded perspective view of a waterproof case for camera apparatus as viewed from a side of a rear face thereof according to the exemplary embodiment of the invention.

DESCRIPTION OF THE EXEMPLARY EMBODIMENT

Hereinafter, a waterproof case for an in-vehicle camera according to the exemplary embodiment of the invention will be described. As a matter of convenience for description, an image side (lens side) is described as a front side, and an imaging area side (imaging device side) is described as rear side.

An in-vehicle camera 10 to which the waterproof case 20 is applied is provided, for example, outside a vehicle body such as a front part of a vehicle, a rear part of a vehicle, or a lateral part of a vehicle. Further, the camera images regions such as a wide region including right and left sides of the front part of a vehicle, a rear region of a vehicle, a left lateral region, or a right lateral region of a vehicle.

The waterproof case 20 includes a case body 21 having a front case part 22 as a first case part and a rear case part 30 as a second case part, and a packing member 40. Further, imaging means is housed and fixed in the front case part 22 and rear case part 30.

Here, the imaging means includes an imaging device 12 and an imaging lens 14.

The imaging device 12 may include, for example, a single CCD etc. The imaging device 12 is mounted and fixed on a substrate 13. A processing circuit including a drive circuit etc. for the imaging device 12 is formed on the substrate 13. Since the substrate 13 is housed and fixed at a predetermined position in the case body 21 including a predetermined position in the front case part 22 and a predetermined position in the rear case part 30, the imaging device 12 is housed and fixed at a predetermined position in the waterproof case 20. Further, a wire connected to the substrate 13 is drawn outward through a wire drawing part formed in the rear case part 30, and is connected to a power source, a control unit, a display apparatus etc.

The imaging lens 14 is a lens designed to conduct light from external region, which is an imaging object, to the imaging device 12 in a desired characteristic. For example, the imaging lens 14 mat be a compound lens in which a plurality of lenses being combined. For a camera which images a periphery of a vehicle, generally, the imaging lens 14 includes a wide-angle lens or a fish-eye lens having a characteristic capable of imaging a scope of wide angle.

The imaging lens 14 is housed and fixed in a lens holding cylinder part 28 of the front case part 22, and is held at a certain position on a front side of the imaging device 12. Accordingly, the imaging device 12 images an external scene through the imaging lens 14.

The front case part 22 is made of a resin, for example, and includes a front case body part 23 and a lens holding cylinder part 28.

The front case body part 23 is formed such that one side (rear side) thereof is opened. Further, a side wall part 24 surrounding all four peripheral sides of the front case body part 23 has a dimension of a predetermined thickness. A packing housing groove 23 b, a concave part 26, and a screw hole 24 h, which will be described below, are formed on a rear opening peripheral part 23 a which is an attaching portion of the front case body part 23.

A lens holding cylinder part 28 is a member that holds the imaging lens 14. Here, the lens holding cylinder part 28 is substantially formed in a cylinder shape, and an inner space thereof is communicated with the front case body part 23. The imaging lens 14 is fixed and held with this lens holding cylinder part 28.

A rear case part 30 is made of a resin, for example, and includes a rear case body part 32 and a flange part 34.

The rear case body part 32 is formed such that one side (front side) thereof is opened. Further, flange part 34 of substantially a rectangular ring-shape is formed on an opening peripheral part of the rear case body part 32 such that the flange part 34 is protected outwardly as an attaching portion. The front case part 22 and the rear case part 30 are attached together such that a rear end face of the front case body part 23 and a front end face of the flange part 34 are facing each other, whereby a rectangular space which houses the imaging means is formed between the front case part 22 and the rear case part 30.

Further, screw insert holes 35 h are formed at certain positions (four corner positions in the exemplary embodiment) of the flange part 34, and screw holes 24 h are formed on the opening peripheral part 23 a of the front case body part 23 at positions corresponding to each of the screw insert holes 35 h. Further, the front case part 22 and the rear case part 30 are fixed and held together by inserting a screw into respective screw insert holes 35 h in a state of being attached to together, and screwing the screw into respective screw holes 24 h. The attachment of the front case part 22 and the rear case part 30 can be performed using various fixing means such as an engagement structure or an adhesive, regardless of the screw.

A packing member 40 is set between the front case part 22 and the rear case part 30. The packing member 40 waterproofs and seals the space between the front case part 22 and the rear case part 30.

More specifically, the packing member 40 is made of elastic member such as rubber, and is formed in a ring shape corresponding to the opening peripheral part 23 a of the front case part 22. In the exemplary embodiment, therefore, the packing member is formed substantially in a rectangular ring shape. On an end face of the opening peripheral part 23 a of the front case part 22, a substantially rectangular ring-shaped packing housing groove 23 b is formed along the circumferential direction of the end face. The packing member 40 is formed in a thickness in which the packing member 40 is housed in the packing housing groove 23 b with some degree of protrusion (small quantity of protrusion in the exemplary embodiment). Further, when the front case body part 23 and the rear case body part 32 are fixed together, the packing member 40 is interposed between the opening peripheral part 23 a and the flange part 34 in a compression state. Accordingly, the space between the opening peripheral part 23 a and the flange part 34 is sealed in a waterproof structure by the packing member 40.

Further, a water preventing section, which prevents the packing member 40 from being exposed to the water outside, is provided in the space between the front case body part 23 and the rear case body part 32.

In the exemplary embodiment, the water preventing section includes a water-stop wall part 36 which is protrudingly formed on an end face of the flange part 34 of the rear case part 30, and a concave part 26 which is formed on an end face of the opening peripheral part 23 a of the front case part 22.

The water-stop wall part 36 is formed on the end face of the flange part 34 so as to project on an outer periphery of the packing member 40 along an extending direction of the packing member 40. In the exemplary embodiment, the water-stop wall part 36 has four protrusions 36 a linearly arranged along an extending directions of each of the four sides of the flange part 34, but the water-stop wall part 36 is not linked in four corners of the flange part 34. Further, each of the protrusions 36 a is formed at an outer peripheral side of a position where the packing member 40 is placed on the flange part 34.

The concave part 26 is formed on an end face of the opening peripheral part 23 a of the front case part 22 in a groove shape capable of fitting the water-stop wall part 36 therein. In the exemplary embodiment, the concave part 26 has four concave grooves 26 a corresponding to a protrusion shape of each of the protrusions 36 a. The concave grooves 26 a have a shape capable of fitting the protrusions 36 a such that a positional relation of the front case body part 23 and the rear case body part 32 is maintained constant when the front case body part 23 and the rear case body part 32 are attached together. Accordingly, in the state of maintaining the front case part 22 and the rear case part 30 in a constant positional relation, the water-stop wall part 36 is adapted to be fitted with respect to the concave part 26. Moreover, it is not necessary that all protrusions 36 a are fitted to each of the concave grooves 26 a without clearance as long as the front case part 22 and the rear case part 30 are maintained in a constant positional relation as a result of an entire fitting structure of the protrusions 36 a and the concave grooves 26 a. For example, each of the protrusions 36 a may be fitted to the respective concave grooves 26 a such that an outer surface of the protrusion 36 a contacts with an outer surface of the concave groove 26 a.

In the waterproof case 20 mentioned above, the packing member 40 is interposed between the opening peripheral part 23 a and the flange part 34 in a compression state when the front case part 22 and the rear case part 30 are fixed together. Accordingly, the front case body part 23 and the rear case body part 32 are sealed in a waterproof structure by the packing member 40. Further, the water-stop wall part 36 is adapted to be fitted to the concave part 26 on the outer peripheral side of the packing member 40.

Accordingly, when washing a car by high pressure, even if high pressure water reaches an attaching portion of the front case part 22 and the rear case part 30 of the waterproof case 20, the high pressure water firstly reaches the water-stop wall part 36. Therefore, the packing member 40 can be prevented from being exposed to the high pressure water. Consequently, a misalignment of the packing member 40 by the high pressure water is efficiently prevented, and an excellent waterproof property can be obtained.

Further, since the water-stop wall part 36 and the concave part 26 are provided within the attaching portion of the front case part 22 and the rear case part 30, a compact structure can be obtained compared with a structure in which high pressure water is prevented by providing an separate member.

Particularly, since the water-stop wall part 36 is fitted to the concave part 26, the clearance between the front case part 22 and the rear case part 30 can be made as small as possible, and an excellent waterproof property can be obtained.

Further, since the water-stop wall part 36 is fitted to the concave part 26 such that the positional relation between the front case part 22 and the rear case part 30 is maintained constant, defects form the positional relation of both case parts 22, 30 can be efficiently prevented.

Assuming that a camera apparatus using the waterproof case 20 is mounted on a vehicle body via a bracket provided on the rear case part 30, and that imaging means including the imaging device 12 and the imaging lens 14 is fixed to the front case part 22. Here, even if the rear case part 30 is mounted to the vehicle body in a proper positional relation, the position of the imaging means with respect to the vehicle becomes misaligned from the proper position when the position of the rear case part 30 and the front case part 22 becomes misaligned. Accordingly, the positional misalignment of the rear case part 30 and the front case part 22 results in a misalignment of imaging scope. Therefore, by fitting the water-stop wall part 36 to the concave part 26 with the positional relation of both case parts 22, 30 being constant, the imaging scope can be maintained constant and a stabilization of quality can be obtained.

Moreover, in the exemplary embodiment, the water-stop wall part 36 is not linked at each of the corners of the flange part 34, that is, the water-stop wall part 36 is intermittently projected from the end face of the flange part 34 at the periphery where the packing member is set. However, the water-stop wall part 36 may be continuously projected from the end face of the flange part 34 at the periphery where the packing member is set. In this case, the packing member 40 can be prevented from being exposed to the high pressure water with respect to a front direction of periphery of the attaching portion, and an excellent waterproof property can be obtained.

Further, although the water-stop wall part 36 is formed in the rear case part 30 and the concave part 26 is formed in the front case part 22 in the exemplary embodiment, the water-stop wall part may be projected and formed in the front case part, and the concave part capable of fitting the water-stop wall part may be formed in the rear case part.

Further, although the water-stop wall part 36 is fitted to the concave part 26 without being externally exposed in the exemplary embodiment, that is not necessarily required. For example, a bottom or an outer side part of the concave part 26 may be opened, and a front end or and outer side face of the water-stop wall part 36 may be externally exposed.

While there has been described in connection with the exemplary embodiment of the present invention, it will be obvious to those skilled in the art that various changes and modification may be made therein without departing from the present invention. It is aimed, therefore, to cover in the appended claim all such changes and modifications as fall within the true spirit and scope of the present invention.

The present invention claims foreign priority from Japanese patent application no. 2005-254416, filed on Sep. 2, 2005, the content of which is incorporated herein by reference. 

1. A waterproof case for an in-vehicle camera comprising: a first case part; a second case part which forms a case body with the first case part so as to house imaging means; a packing member set between the first case part and the second case part; and a water preventing section provided between the first case part and the second case part, wherein the packing member waterproofs and seals the space between the first case part and the second case part, and the water preventing section prevents the packing member from being exposed to water outside.
 2. The waterproof case for an in-vehicle camera according to claim 1, wherein the water preventing section comprises: a water-stop wall part protrudingly formed on an attaching portion of the first case part at an outer peripheral of the packing member; and a concave part formed on an attaching portion of the second case part, wherein the water-stop wall part can be fitted in the concave part.
 3. The waterproof case for an in-vehicle camera according to claim 2, wherein the water-stop wall part is fitted to the concave part such that a positional relation of the first case part and the second case part is maintained constant.
 4. The waterproof case for an in-vehicle camera according to claim 2, wherein the first case part includes a lens holding cylinder part which holds a imaging lens of the in-vehicle camera.
 5. The waterproof case for an in-vehicle camera according to claim 2, wherein the second case part includes a lens holding cylinder part which holds a imaging lens of the in-vehicle camera.
 6. The waterproof case for an in-vehicle camera according to claim 1, wherein the water preventing section is provided at an outer peripheral of the packing member.
 7. The waterproof case for an in-vehicle camera according to claim 1, wherein a packing housing groove is formed on one of the first case part or the second case part, further wherein the packing member is housed in the packing housing groove such that the packing member protrudes from the packing housing groove.
 8. The waterproof case for an in-vehicle camera according to claim 1, wherein the first case part and the second case part are fixed together with a screw.
 9. The waterproof case for an in-vehicle camera according to claim 2, wherein the water-stop wall part is intermittently projected from the attaching portion of the first case part. 